Various display devices have been developed and are being used. A liquid crystal display device which realizes images using liquid crystal is widely used.
Generally, a liquid crystal display (LCD) includes two display panels and a liquid crystal layer disposed therebetween and having a dielectric anisotropy. An electric filed is formed in the liquid crystal layer, and a transmittance of light passing the liquid crystal layer is regulated by regulating amplitude of the electric field so as to obtain a desired image. Such a liquid crystal display is representative one of a flat panel display (FPD), and TFT-LCD which uses thin film transistor (TFT) as a switching element is widely used.
A plurality of display signal lines i.e., gate lines and data lines, a plurality of thin film transistors and pixel electrodes are formed on a lower display panel of the two display panels of the liquid crystal display panel, and a color filter and a common electrode are formed on a upper display panel.
Such a liquid crystal display panel is generally manufactured in a flat shape, so the conventional liquid crystal display panel cannot be used as a curved display.
In order to solve this problem, a flexible liquid crystal display panel which has flexible substrates instead of glass substrates of a conventional liquid crystal display panel so as to be bent by external bending force has been developed.
However, there is a problem that the manufacturing process of the conventional flexible liquid crystal display panel is difficult and the manufacturing cost thereof is high.
Conventionally, in order to realize a multi-layered image with a depth, a method of overlapping a plurality of liquid crystal display (LCD) panels has been introduced.
In this case, there is a problem that a noise (interference pattern) such as wood grain and water wave due to the interference between the overlapped LCD panels occurs. That is, if a plurality of LCD panels having cross stripes by pixels are closely disposed, a noise occurs by the Moire phenomenon.
Technologies for preventing such noises have been introduced. For example, in Korean Patent registration No. 10-0614419 (Applicant: deep video imaging limited, Title of the invention: Multi-layered display), a diffuse layer for diffusing light is interposed between two LCD panels to remove noise by the overlap of the LCD panels.
However, in case of interposing a diffuse layer between two LCD panels, a process of disposing the diffuse layer between the LCD panels and then assembling the same is required, so an additional assembling process is required and the productivity is deteriorated.